Pacquiao vs. Mayweather: Dream Showdowns Fans Need to See in Their Lifetime

Manny Pacquiao will face Juan Manuel Marquez tonight at the MGM Grand and, frankly, no one cares. We, and by "we" I mean the sports world at large, want to see Pacquiao face Floyd Mayweather Jr.

No number of sound clips or sucker punches or warm-up fight antics will change that. We want, we need Manny vs. Floyd.

Nothing makes the sports world spin like two superstars going mano a mano. The tantalizing possibility of greatness rarely hangs so heavily in the air.

With that in mind, we dug up five great player matchups that sports fans crave. May the fates and playoff brackets conspire to bring them forth.

LeBron James vs. Kobe Bryant

The window is closing fast on the possibility of a LeBron-Kobe NBA final.

In 2009, LeBron's Cavaliers bowed out in the conference final to the Orlando Magic and left the Lakers hanging. Last year, Kobe couldn't get his Lakers past Dallas in the second round.

Now one has to wonder whether a 33-year-old Bryant has enough in the tank to get L.A. back to the finals.

But oh, how sweet it would be Kobe if could summon enough Black Mamba magic to meet LeBron in an NBA finals showdown.

The two greatest players of the post-Michael Jordan era, the two men most commonly mentioned in the same breath as his Airness, facing off in a duel for historic bragging rights. 

Both would need the win for their legacy, Kobe in order to enter the Jordan conversation and LeBron in order to prove he can win the big game.

Meeting in some Christmas Day special won't do it, gentlemen. We need a seven-game fistfight worthy of Magic and Bird. We need Kobe in the isolation with the Lakers down one and 20 seconds remaining.

We need LeBron stepping out to the perimeter and telling Wade, "That's my man."

Sidney Crosby vs. Alexander Ovechkin

It's true, Alexander Ovechkin and Sidney Crosby already met once in the playoffs. Back in 2009, they battled through an epic seven-game Conference Semifinal that eventually launched Crosby and the Penguins to a Stanley Cup victory.

While that was awesome, it only whetted my appetite for more. Enough of this Conference Semifinal stuff, let's see Crosby and Ovechkin duel with a Cup berth on the line.

The two men anointed as hockey's co-saviors have largely lived up to that hype, and an Eastern Conference Final showdown would propel the sport toward new heights.

The Penguins and Capitals are both good enough to make that happen. They also seem to hate each other enough to add another layer of intrigue to this delicious potential match-up.

So let's hope Crosby makes a full concussion recovery, Ovechkin continues to do crazy things with hockey pucks and that the two young wizards treat us to a hockey series for the ages.

Manny Pacquiao vs. Floyd Mayweather

The recent death of boxing great Joe Frazier brought the need for a Pacquiao-Mayweather fight into even greater focus.

When Frazier battled Muhammad Ali for the heavyweight crown in 1971, the two warriors elevated both themselves and their sport. They showed that boxing, unlike any other game, feeds off the cult of personality.

Frazier and Ali struck a powerful contrast, the yeoman from Philadelphia versus the revolutionary from Louisville. Those personality differences imbued their ringside theatrics with a dramatic twist only boxing can capably deliver.

That's what makes the sport great. That's what the quiet Filipino punisher and the flamboyant American master can deliver.

With UFC encroaching on boxing's place as the world's favorite pugilistic pastime, the need for Pacquiao vs. Mayweather grows stronger by the day. It's both flagrantly dramatic and entirely true to say the fate of boxing hangs in the balance.

Tom Brady vs. Aaron Rodgers

Already the heir apparent to Peyton Manning as the NFL's most prolific passer, it's time for Aaron Rodgers to step into Manning's role as Tom Brady's chief rival.

Rodgers' Packers and Brady's Patriots ought to stay in the Super Bowl picture for the next few years, giving sports fans hope that the two could meet on America's biggest stage. 'Twould be quite a sight.

Brady carries his legacy to battle, hoping that a fourth Super Bowl might solidify him as the greatest signal caller ever. Rodgers carries his ambition, the chance that he may finally, fully emerge from Brett Favre's shadow and inject himself into future GOAT conversations.

You also have to appreciate that a Brady-Rodgers Super Bowl would probably involve a lot of points. America loves points.

Yoenis Cespedes vs. Bryce Haper

I admit it's far-fetched to anticipate a duel between two players who've never played big league baseball, but the possibilities are ticklishly exciting.

Harper was the greatest amateur prospect since Alex Rodriguez, and the one with the most raw power. Baseball's been counting down to his arrival since the prep superstar skipped his senior year of high school in order to enter the draft early.

If you don't already know about Cespedes, read up. The Cuban defector recently set the Cuban league record for home runs in a season and set the baseball world afire with this workout video.

He has a linebacker's build, a slap-hitter's hand-eye and the kind of mystique that's only possible from playing years behind the Cuban curtain.

Needless to say, major league teams are furiously courting Cespedes the same way the Nationals broke the bank to sign Harper in 2010.

To see the two five-tool marvels of the baseball world square off in a playoff series, or even just a home run derby, would be the casual fan's delight.

Who Else?

Who else would you like to see in an athletic super-duel?

Derrick Rose vs. Kevin Durant?

Blake Griffin vs. Dwight Howard?

Michael Phelps vs. Ryan Lochte?

Larry Fitzgerald vs. Andre or Calvin Johnson?

Leave your suggestions in the comments, and debate away.